Yeah, we'll see where that goes. He has been interviewed at least once that I know of, and likely more than once by more than one agency. Once GBI came onboard, things moved pretty fast.
As for the conversation regarding a "burglary", OCGA 16-7-1 lays it out (try Justia.com to read it for yourself), but the basic elements of a burglary are that a person "without authority", "with the intent to commit a theft or felony therein", "enters or remains in a ________ ." (several options here).
So, wrt Mr. Arbery, he did enter...and we can assume without authority. Problem is, there's no evidence at all of "intent to commit a theft or felony therein." Two out of three is good in baseball, but it won't net you a burglary arrest in Georgia.
No burglary. Plain and simple. Criminal Trespass? Maybe, but only if (a) he had been previously warned by the property owner or law enforcement not to enter the property, or (b) it was properly posted. On that point, I don't know the facts, but if there's no burglary, there's no legal citizens arrest, and at that point you're trying to make chicken salad out of chicken sh*t.
And lest we forget, Georgia law allows for resistance to what is believed to be an illegal arrest. Not much noise on here about that little nugget.
Take a deep breath, and let this all play out. Like I said before, it's about to get interesting in these parts...